Using argument objects to implement overloading in JavaScript (overload)

Some concepts:

Overload (Overload):
What is: the same function name, a number of different parameter list functions, when called, according to the different parameters, automatically select the corresponding function call!
Why: Lighten the burden of the caller, a function name that can perform a variety of operations
When: a task, according to the different parameters, the implementation of different operating procedures
How to: JS syntax does not support overloading effects
WORKAROUND: Within all function objects, an automatically built-in

The following functions are implemented:

function Pay () {  console.log ("Payment");} function Pay (num) {  console.log ("cash payment");} function Pay (card,pwd) {  console.log ("swipe paid");} The    following are the ideal overloads to achieve the effect of pay  ()  //"payment" paid (500)//"Cash paid" pay ("xxxxxxxxxxxxx", "546464")//Credit card payment//    and due to The declaration advance feature in JavaScript will result in the actual output of the following result pay ()/  /Swipe Pay (500)//swipe to pay ("xxxxxxxxxxxxx", "546464")//Credit card payment

　　

So we need arguments objects in JavaScript to simulate overloaded effects

Concept two:

Within all function objects, a arguments object is automatically built in
Arguments object:
Class Array object that specifically holds all parameter values passed in to the function
Class Array object: (object like array)
VS array: Same: subscript, length, for traversal
Different: Class array objects are object, not array, cannot use array's API
Array is an array type and can use all the API

The resulting solution is as follows:

function Pay () {       if (arguments[0]==null) {           console.log ("payment");       } else if (typeof (Arguments[0]) = = "Number") {           console.log ("cash payment, receive you" +arguments[0]+ "Yuan");       } else{           console.log ("swipe payment, your card number" +arguments[0]+ "debit Success");}    }    Pay (); Paid pay    (500);//cash payment, your 500 yuan pay    ("14564645646");//Credit card payment, your card number 14564645646 debit Success

Of course, the use of arguments objects far more than this one, here is a simple introduction.

Using argument objects to implement overloading in JavaScript (overload)